media/base/video_util.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/base/video_util.h"
   6
   7 #include <cmath>
   8
   9 #include "base/logging.h"
  10 #include "media/base/video_frame.h"
  11 #include "media/base/yuv_convert.h"
  12
  13 namespace media {
  14
  15 gfx::Size GetNaturalSize(const gfx::Size& visible_size,
  16                          int aspect_ratio_numerator,
  17                          int aspect_ratio_denominator) {
  18   if (aspect_ratio_denominator == 0 ||
  19       aspect_ratio_numerator < 0 ||
  20       aspect_ratio_denominator < 0)
  21     return gfx::Size();
  22
  23   double aspect_ratio = aspect_ratio_numerator /
  24       static_cast<double>(aspect_ratio_denominator);
  25
  26   int width = floor(visible_size.width() * aspect_ratio + 0.5);
  27   int height = visible_size.height();
  28
  29   // An even width makes things easier for YV12 and appears to be the behavior
  30   // expected by WebKit layout tests.
  31   return gfx::Size(width & ~1, height);
  32 }
  33
  34 void CopyPlane(size_t plane, const uint8* source, int stride, int rows,
  35                VideoFrame* frame) {
  36   uint8* dest = frame->data(plane);
  37   int dest_stride = frame->stride(plane);
  38
  39   // Clamp in case source frame has smaller stride.
  40   int bytes_to_copy_per_row = std::min(frame->row_bytes(plane), stride);
  41
  42   // Clamp in case source frame has smaller height.
  43   int rows_to_copy = std::min(frame->rows(plane), rows);
  44
  45   // Copy!
  46   for (int row = 0; row < rows_to_copy; ++row) {
  47     memcpy(dest, source, bytes_to_copy_per_row);
  48     source += stride;
  49     dest += dest_stride;
  50   }
  51 }
  52
  53 void CopyYPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  54   CopyPlane(VideoFrame::kYPlane, source, stride, rows, frame);
  55 }
  56
  57 void CopyUPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  58   CopyPlane(VideoFrame::kUPlane, source, stride, rows, frame);
  59 }
  60
  61 void CopyVPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  62   CopyPlane(VideoFrame::kVPlane, source, stride, rows, frame);
  63 }
  64
  65 void CopyAPlane(const uint8* source, int stride, int rows, VideoFrame* frame) {
  66   CopyPlane(VideoFrame::kAPlane, source, stride, rows, frame);
  67 }
  68
  69 void MakeOpaqueAPlane(int stride, int rows, VideoFrame* frame) {
  70   int rows_to_clear = std::min(frame->rows(VideoFrame::kAPlane), rows);
  71   memset(frame->data(VideoFrame::kAPlane), 255,
  72          frame->stride(VideoFrame::kAPlane) * rows_to_clear);
  73 }
  74
  75 void FillYUV(VideoFrame* frame, uint8 y, uint8 u, uint8 v) {
  76   // Fill the Y plane.
  77   uint8* y_plane = frame->data(VideoFrame::kYPlane);
  78   int y_rows = frame->rows(VideoFrame::kYPlane);
  79   int y_row_bytes = frame->row_bytes(VideoFrame::kYPlane);
  80   for (int i = 0; i < y_rows; ++i) {
  81     memset(y_plane, y, y_row_bytes);
  82     y_plane += frame->stride(VideoFrame::kYPlane);
  83   }
  84
  85   // Fill the U and V planes.
  86   uint8* u_plane = frame->data(VideoFrame::kUPlane);
  87   uint8* v_plane = frame->data(VideoFrame::kVPlane);
  88   int uv_rows = frame->rows(VideoFrame::kUPlane);
  89   int u_row_bytes = frame->row_bytes(VideoFrame::kUPlane);
  90   int v_row_bytes = frame->row_bytes(VideoFrame::kVPlane);
  91   for (int i = 0; i < uv_rows; ++i) {
  92     memset(u_plane, u, u_row_bytes);
  93     memset(v_plane, v, v_row_bytes);
  94     u_plane += frame->stride(VideoFrame::kUPlane);
  95     v_plane += frame->stride(VideoFrame::kVPlane);
  96   }
  97 }
  98
  99 static void LetterboxPlane(VideoFrame* frame,
 100                            int plane,
 101                            const gfx::Rect& view_area,
 102                            uint8 fill_byte) {
 103   uint8* ptr = frame->data(plane);
 104   const int rows = frame->rows(plane);
 105   const int row_bytes = frame->row_bytes(plane);
 106   const int stride = frame->stride(plane);
 107
 108   CHECK_GE(stride, row_bytes);
 109   CHECK_GE(view_area.x(), 0);
 110   CHECK_GE(view_area.y(), 0);
 111   CHECK_LE(view_area.right(), row_bytes);
 112   CHECK_LE(view_area.bottom(), rows);
 113
 114   int y = 0;
 115   for (; y < view_area.y(); y++) {
 116     memset(ptr, fill_byte, row_bytes);
 117     ptr += stride;
 118   }
 119   if (view_area.width() < row_bytes) {
 120     for (; y < view_area.bottom(); y++) {
 121       if (view_area.x() > 0) {
 122         memset(ptr, fill_byte, view_area.x());
 123       }
 124       if (view_area.right() < row_bytes) {
 125         memset(ptr + view_area.right(),
 126                fill_byte,
 127                row_bytes - view_area.right());
 128       }
 129       ptr += stride;
 130     }
 131   } else {
 132     y += view_area.height();
 133     ptr += stride * view_area.height();
 134   }
 135   for (; y < rows; y++) {
 136     memset(ptr, fill_byte, row_bytes);
 137     ptr += stride;
 138   }
 139 }
 140
 141 void LetterboxYUV(VideoFrame* frame, const gfx::Rect& view_area) {
 142   DCHECK(!(view_area.x() & 1));
 143   DCHECK(!(view_area.y() & 1));
 144   DCHECK(!(view_area.width() & 1));
 145   DCHECK(!(view_area.height() & 1));
 146   DCHECK(frame->format() == VideoFrame::YV12 ||
 147          frame->format() == VideoFrame::I420);
 148   LetterboxPlane(frame, VideoFrame::kYPlane, view_area, 0x00);
 149   gfx::Rect half_view_area(view_area.x() / 2,
 150                            view_area.y() / 2,
 151                            view_area.width() / 2,
 152                            view_area.height() / 2);
 153   LetterboxPlane(frame, VideoFrame::kUPlane, half_view_area, 0x80);
 154   LetterboxPlane(frame, VideoFrame::kVPlane, half_view_area, 0x80);
 155 }
 156
 157 void RotatePlaneByPixels(
 158     const uint8* src,
 159     uint8* dest,
 160     int width,
 161     int height,
 162     int rotation,  // Clockwise.
 163     bool flip_vert,
 164     bool flip_horiz) {
 165   DCHECK((width > 0) && (height > 0) &&
 166          ((width & 1) == 0) && ((height & 1) == 0) &&
 167          (rotation >= 0) && (rotation < 360) && (rotation % 90 == 0));
 168
 169   // Consolidate cases. Only 0 and 90 are left.
 170   if (rotation == 180 || rotation == 270) {
 171     rotation -= 180;
 172     flip_vert = !flip_vert;
 173     flip_horiz = !flip_horiz;
 174   }
 175
 176   int num_rows = height;
 177   int num_cols = width;
 178   int src_stride = width;
 179   // During pixel copying, the corresponding incremental of dest pointer
 180   // when src pointer moves to next row.
 181   int dest_row_step = width;
 182   // During pixel copying, the corresponding incremental of dest pointer
 183   // when src pointer moves to next column.
 184   int dest_col_step = 1;
 185
 186   if (rotation == 0) {
 187     if (flip_horiz) {
 188       // Use pixel copying.
 189       dest_col_step = -1;
 190       if (flip_vert) {
 191         // Rotation 180.
 192         dest_row_step = -width;
 193         dest += height * width - 1;
 194       } else {
 195         dest += width - 1;
 196       }
 197     } else {
 198       if (flip_vert) {
 199         // Fast copy by rows.
 200         dest += width * (height - 1);
 201         for (int row = 0; row < height; ++row) {
 202           memcpy(dest, src, width);
 203           src += width;
 204           dest -= width;
 205         }
 206       } else {
 207         memcpy(dest, src, width * height);
 208       }
 209       return;
 210     }
 211   } else if (rotation == 90) {
 212     int offset;
 213     if (width > height) {
 214       offset = (width - height) / 2;
 215       src += offset;
 216       num_rows = num_cols = height;
 217     } else {
 218       offset = (height - width) / 2;
 219       src += width * offset;
 220       num_rows = num_cols = width;
 221     }
 222
 223     dest_col_step = (flip_vert ? -width : width);
 224     dest_row_step = (flip_horiz ? 1 : -1);
 225     if (flip_horiz) {
 226       if (flip_vert) {
 227         dest += (width > height ? width * (height - 1) + offset :
 228                                   width * (height - offset - 1));
 229       } else {
 230         dest += (width > height ? offset : width * offset);
 231       }
 232     } else {
 233       if (flip_vert) {
 234         dest += (width > height ?  width * height - offset - 1 :
 235                                    width * (height - offset) - 1);
 236       } else {
 237         dest += (width > height ? width - offset - 1 :
 238                                   width * (offset + 1) - 1);
 239       }
 240     }
 241   } else {
 242     NOTREACHED();
 243   }
 244
 245   // Copy pixels.
 246   for (int row = 0; row < num_rows; ++row) {
 247     const uint8* src_ptr = src;
 248     uint8* dest_ptr = dest;
 249     for (int col = 0; col < num_cols; ++col) {
 250       *dest_ptr = *src_ptr++;
 251       dest_ptr += dest_col_step;
 252     }
 253     src += src_stride;
 254     dest += dest_row_step;
 255   }
 256 }
 257
 258 gfx::Rect ComputeLetterboxRegion(const gfx::Rect& bounds,
 259                                  const gfx::Size& content) {
 260   // If |content| has an undefined aspect ratio, let's not try to divide by
 261   // zero.
 262   if (content.IsEmpty())
 263     return gfx::Rect();
 264
 265   int64 x = static_cast<int64>(content.width()) * bounds.height();
 266   int64 y = static_cast<int64>(content.height()) * bounds.width();
 267
 268   gfx::Size letterbox(bounds.width(), bounds.height());
 269   if (y < x)
 270     letterbox.set_height(static_cast<int>(y / content.width()));
 271   else
 272     letterbox.set_width(static_cast<int>(x / content.height()));
 273   gfx::Rect result = bounds;
 274   result.ClampToCenteredSize(letterbox);
 275   return result;
 276 }
 277
 278 void CopyRGBToVideoFrame(const uint8* source,
 279                          int stride,
 280                          const gfx::Rect& region_in_frame,
 281                          VideoFrame* frame) {
 282   const int kY = VideoFrame::kYPlane;
 283   const int kU = VideoFrame::kUPlane;
 284   const int kV = VideoFrame::kVPlane;
 285   CHECK_EQ(frame->stride(kU), frame->stride(kV));
 286   const int uv_stride = frame->stride(kU);
 287
 288   if (region_in_frame != gfx::Rect(frame->coded_size())) {
 289     LetterboxYUV(frame, region_in_frame);
 290   }
 291
 292   const int y_offset = region_in_frame.x()
 293                      + (region_in_frame.y() * frame->stride(kY));
 294   const int uv_offset = region_in_frame.x() / 2
 295                       + (region_in_frame.y() / 2 * uv_stride);
 296
 297   ConvertRGB32ToYUV(source,
 298                     frame->data(kY) + y_offset,
 299                     frame->data(kU) + uv_offset,
 300                     frame->data(kV) + uv_offset,
 301                     region_in_frame.width(),
 302                     region_in_frame.height(),
 303                     stride,
 304                     frame->stride(kY),
 305                     uv_stride);
 306 }
 307
 308 }  // namespace media